Marine railway.



No. 694,9. Patented Mar. 4, I902.

, J. L. CBANDAL L.

I MARINE RAILWAY. (Aplication filed Aug. 31, 1901.

(No Model.)

ll/i'inesaee:

1n: Norms PETERS cu. PHoTo-Lm-la, WASHINGTON a, c.

. UNITE STATE PAT NT" OFFICE.

JAMES L. CRANDALL, OF BOSTON, MASSACHUSETTS, ASSIGNOR TO H. I. CRANDALL & SON COMPANY, OF BOSTON, MASSACHUSETTS, Av COR- PORATION OF MAINE.

MARINE RAILWAY.

' SPEGIIEECAEIQN forming part of Letters Patent No. 694,911, dated March 4, 1902.

Application filed August 31 1 901. Serial Notfi3y8 9- (No model.) 7

To all whom it may concern:

Be it known that I, J AMES L. CRANDALL, of Boston, in the county of Suffolk and State of Massachusetts, have invented an Improvementin Marine Railways, of which the following description, in "connection with the accompanying drawings, is a specification, like lettors on the drawings representing like parts.

This invention relates to marine railways, sometimes called slipways or patent slips, and has for its object to improve and simplify the construction of the means employed for hauling in or along the cradle, to the end that the strain upon each chain of number of chains employed may be equalized, even though the chains or the links thereof vary slightly in length.

The invention'is particularly applicable in cases where a number of chains are employed as the means of haulingin or'along the cradle-- Figure 1 shows in diagram a cradle and means embodying this inventionfor hauling it along, comprising bridle-chains connected to theeradle-inopposite ways and two actuating-chains .eaeh connected with both bridlechains and means'for equalizing the strain or pull of said actuating-chains. Fig. 2 is an enlarg-cd view showing one of the bridle-chains and a portion of the two actuating-chains.

n represents in diagram a cradle which may be of any usualor suitable construction. To the cradle a two bridle-chains are attached in opposite ways, said chains being herein shown as made alike and each comprising a chain 0,, attached at its end to the cradle a, as at a a and at a point intermediate its length passing around a chain-wheel a which is supported by a bare or other suitable support connected with the-cradle, as at a. Each bridle-chain a at a point between each end and the chain-wheel (1 passes around a chainwheel a connected to a bar or other support l are made alike, or substantially so. The actuating-chain b is herein shown as made as an endless chain and passes around one of the chain wheels a at or near one endot the cra- -dle and over two chain-wheels c'c which are rigidly secured to a driving-shat t a and along the under side of the cradle to a point at or near the opposite end thereofland then around two idle chain-wheels cl d, loosely mounted on a shaft "61 or otherwise supported, and around one of the chain-wheels d at said opposite end of the cradle. The other actuating-chain c is likewise herein shown as made as an endless chain and passes around the other chain-wheel a at or near one end of the cradle and over two chain-wheels c rigidly secured to the-driving-shaft c and along the under side of the cradle to a point at or near the opposite end thereof, and then around two idle chain-wheels d d, loosely mounted on the shaft (Z and around the other chainwheel a at said opposiie eud of the cradle. As the drivingshatt c is turned the actuating-chains b and 0 will be simultaneously operated and the cradle moved along in one or the other-direction, and the strain orpull with the cradle will be equalized. It will be understood thatthe chains employed for this purpose are large, and while they may comprise the same number of links, yetin prac: tice they will vary in length; but by the means herein provided this difference will be readily compensated for.

I claim 7 1. In an apparatus of the kind described,

ing around a chain-wheel also connected with the cradle, and also passing around two chainwheels, as a, disposed between said chainwheel and the points of attachment of the chain to the cradle, and two actuating-chains passing around other chain-wheels, the supports of which are connected to said chainwheels a and also passing around chainwheels rigidly secured to a driving-shaft, substantially as described. v

2. In an apparatus of the kind described, two bridle-chains connected respectively to upon the bridle-chains which are connected,

abridle-cliain connected to the cradle, passthe cradle in opposite Ways, each passing a driving-shaft, and also around idle chainno around a chain-wheel also connected with the Wheels, substantially as described.

' cradle, and also around two chain-wheels, as In testimony whereof I have signed my afldisposed between the aforesaid chain-Wheel name to this specification in the presence of and the points of attachment of the chain to two subscribing witnesses.

the cradle, and two actuating-chains passing I JAMES L. CRANDALL. around other chain-wheels, the supports of Witnesses: which are connected to'said chain-wheels a, B. J. NQYES,

and around chain-Wheels rigidly secured to H. B. DAVIS. 

